Atka volcanic complex reported activity

Event Name : Korovin 1986/5

Start:

May 23, 1986

Observed

Central eruption:
Phreatic:

Eruption Type:	Explosive
MaxVEI:	1
ColHeight:	600 m

Description: From Miller and others (1998): "Steam emission was observed in early May, 1986, and on May 23rd a 600 m steam plume containing some ash reportedly occurred soon after a 7.7 magnitude earthquake struck about 100 km to the southwest (Smithsonian Institution, 1986)."

From Smithsonian Institution (1986): "On 6 May], James Dickson noted a 500-m vertical steam plume over the SE part of the summit [of Korovin]. On 23 May at about 1730, Aleutian Air pilot Thomas Madsen noted a 600-m steam plume containing traces of ash rising above the rim of a 240-m-deep crater in the SE part of the summit area. A shallow magnitude 7.7 earthquake centered roughly 100 km [SSW] of Korovin at [51.52N, 174.78W] occurred 7 May [at 2247 GMT].

John Reeder and Kirk Swanson climbed [Korovin] in July 1983, observing only minor steaming from deep within the crater, rising to only 60 m above its floor."

Reeder (1989) adds the following information: "Pilot Harold Wilson of Peninsula Airways Inc. on 17 December 1986 observed an impressive above average steam plume from Korovin volcano that contained no detectable ash. The steam plume completely filled the crater of the volcano and it rose to a 2,250 m altitude (above 800 m above the crater rim) as measured by his Piper T1040 Navaho altimeter."